Primary prevention of diseases- what is it, why needed and how to do it?

1. DISEASE PREVENTION
STRATEGIES: PRIMARY
Health Sciences Module
BPH- 2nd year
Dr Tanveer Rehman
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2. Introduction
■ Natural history of a disease - five stages: underlying,
susceptible, subclinical, clinical, and recovery/disability/death
■ Corresponding preventive health measures – grouped into
similar stages to target the prevention of these stages of a
disease
■ Primordial, primary, secondary, and tertiary prevention
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Pathogenesis

5. Primary prevention
■ Aims to prevent disease or injury before it ever occurs
■ Target population: Healthy individuals
■ Done by preventing exposures to hazards that cause
disease or injury, altering unhealthy or unsafe behaviours
that can lead to disease or injury, and increasing resistance
to disease or injury should exposure occur
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6. Significance
■ Action taken before the onset of disease
■ Intervention in the pre- pathogenesis phase of a disease or
health problem
■ Preventive services are proven to be an essential aspect of
healthcare – however, they appear consistently underutilized
in our country
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7. Significance…
■ With cost, time, and resource constraints on physicians,
many preventive services get overlooked for patients
■ Physicians need to remain up to date on the prevention
guidelines and ensure all are offered appropriate services
■ Includes concept of “positive health” – achievement &
maintenance of acceptable level of health
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8. Examples
■ Legislation and enforcement to ban or control the use of
hazardous products (e.g. asbestos) or to mandate safe and
healthy practices (e.g. use of seatbelts and bike helmets)
■ Education about healthy and safe habits (e.g. eating well
(supplementation), exercising regularly, not smoking)
■ Immunization against infectious diseases
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9. Modes of intervention
Two ways to achieve it
1. Health promotion
2. Specific protection
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10. Health Promotion
Process of enabling
people to increase control
over the determinants of
health and thereby improve
their overall health
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11. Health Promotion
Can be achieved by following interventions
■ Health education
■ Environmental modification
■ Behavioural changes
■ Lifestyle changes
■ Nutritional intervention
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12. Specific protection
■ Efforts directed toward protection against specific diseases
■ Immunization
■ Use of specific nutrients
■ Chemoprophylaxis (e.g. Rifampicin for leprosy)
■ Protection against accidents / occupational hazards
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13. Approaches
WHO has recommended the following approaches for primary
prevention of chronic diseases where the risk factors are
established:
■ Population (mass) strategy
■ High-risk strategy
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14. Population (mass) strategy
■ Directed at the whole population (masses) irrespective of
individual risk levels – sick individuals & sick population
(Rose hypothesis)
■ Directed towards socio-economic, and lifestyle changes
■ Example: even a small reduction in the average blood
pressure/ serum cholesterol of a population would produce a
large reduction in incidence of cardiovascular diseases
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15. High-risk strategy
■ Aims to bring preventive care to individuals at special risk
■ Requires detection of individuals at high risk by the optimum
use of clinical methods
■ Primary prevention is a “Holistic” approach which relies on
the measures taken to promote health
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17. THANK YOU
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